Sweeping by a moving solid

We have reduced the problem of a swept solid
description to a global extremum search by a parameter of movement.
It allows the user to apply arbitrary variable-shape and CSG solids as generators,
arbitrary parametrized movement and self-intersections. An example of sweeping
by falling cup and spoon is shown below.

Simulation of NC machining uses time-dependent set-theoretic operations
with a part and a cutter in relative motion: